The fiends are a demonic race that are notable for having a face on their chest, six horns coming out of their cylindrical head, a mouth full of large jagged teeth which almost completely circle their head, a small goatee, and a diamond shaped jewel lodged in their forehead. They also have spines coming out of the back part of their hooves and hands.

Fiends have wings and cloven feet with a general build to that of daemons and ered'ruin — which may imply that they are a subspecies of the ered'ruin species. Some fiends also hold the rank of doomguard, such as the fiend known as Overmaster Grindgarr, which may also prove to be a connection to the ered'ruin.